JP2008525077A - Blood circulation assist device - Google Patents

Abstract

  The blood circulation assistance device (1) has one or more cuff elements (3) that form a chamber for containing a blood conduit (6). The chamber is open at both ends of one or more cuff elements (3) and is configured such that a blood conduit (6) extends therethrough. An opening (22) is provided on the side of the one or more cuff elements (3) between each end of the chamber to place one or more cuff elements (3) around the blood conduit (6). The one or more cuff elements (3) have two inwardly expandable inflatable elements (4, 5) for squeezing the blood conduit (6). The inflatable elements (4, 5) are arranged diametrically opposite each other across the chamber.

Description

  The present invention relates to a blood circulation assist device and a method for performing counterpulsation (particularly diastolic counterpulsation).

Mechanical circulatory assistance is increasingly used in the management of heart failure. In particular, a ventricular assist device (VAD) placed in parallel with the native ventricle provides hemodynamic assistance for patients waiting for a heart transplant (bridging to transplant) ¹ , and also restores natural myocardial function ( a bridge to recovery) ^2. More recently, VAD has been considered as an alternative to heart transplant (destination therapy) ³ . Complete artificial heart ⁴ is not widely used compared to VAD. In the case of a complete artificial heart, it is necessary to remove the living heart, but it is designed as a bridge to transplantation and for permanent use (destination therapy). Has been. Because VAD and fully artificial hearts involve contact with blood, it is absolutely necessary to continue anticoagulant treatment on patients to minimize the risk of blood clotting (thrombosis) .

Intra-aortic balloon counterpulsation (IABC) ⁵ is a widely used treatment and is mainly used in the case of acute heart failure. Insertion of an intra-aortic balloon (IAB) is relatively non-invasive to VAD, but because patients are non-ambulant, assistance duration is usually limited to less than a few weeks, and risk of arterial inserting the IAB catheter leading to blockage and lower limb ischemia is high ^6. Since VABs and IAB catheters come into contact with blood as well as VADs and complete artificial hearts, patients need to receive anticoagulant treatment continuously.

  WO-A-02 / 24254 discloses a new fully implantable extravascular (non-blood contact) counterpulsator suitable for long term use in ambulatory patients with a high performance electrohydraulic energy converter. . The energy converter has an impeller that rotates about an axis to drive fluid and reciprocates axially to change the position of the impeller itself. That is, the operating principle is as follows. When the diastole begins, the energy converter delivers working fluid from an integral internal reservoir (described in US-A-5,346,458) into a peri-aortic jacket, This compresses the aorta and moves blood proximally (towards the heart) and distally (away from the heart). This has the effect of increasing diastolic blood pressure, improves organ perfusion (especially myocardial perfusion) and receives most of the blood supply during diastole. At the end of diastole, the direction in which the energy converter delivers hydraulic drive fluid quickly reverses, resulting in a peri-aortic jacket contraction and a decrease in end-diastolic arterial blood pressure (the pre- systolic dip)). This reduces the amount of work the heart needs to do during the next pulsatile ejection phase (systole).

  One problem with this type of energy converter is that a corresponding reaction occurs in the remainder of the counterpulsator device due to the reciprocating axial movement of the impeller. This reaction may cause the counterpulsator device to move relative to the aorta and cause aortic trauma.

  WO-A-02 / 24254 also discloses an alternative means for realizing extraaortic counterpulsation with a solid actuator directly connected to the aorta.

  Most importantly, the aorta within the periaortic jacket can withstand repeated deformations over time without causing mechanical failure or harmful tissue remodeling of the aorta. Furthermore, it is highly desirable that the configuration of the implantable system be compatible with surgical procedures that minimize trauma. The present invention seeks to meet one or more of these requirements, and in an important aspect, the performance of each embodiment of the present invention exceeds that of the highest performance IAB system currently available. Was found (see FIG. 19).

  In one aspect thereof, the present invention is a blood circulation assistance device having one or more cuff elements forming a chamber for containing a blood conduit, the chamber being at each end of the one or more cuff elements. Open and the blood conduit is configured to extend therethrough, the one or more cuff elements including at least one inwardly-expandable inflatable element for compressing the blood conduit. A blood circulation assist device having an expanding inflatable element is provided.

  Conveniently, an opening is provided on one side of the one or more cuff elements between each end of the chamber for placing the one or more cuff elements around a blood conduit.

  In some embodiments, one inflatable element is provided.

  Preferably there are at least two or exactly two inwardly expandable elements. In some embodiments, a set (eg, two) of inflatable elements work together and actually operate as a single inflatable element. As used herein, an “expandable element” includes a set of expandable elements that operate in conjunction.

  Advantageously, the inflatable elements are arranged diametrically opposite each other across the chamber.

  In the present specification, the terms “oppositely opposite” and “exactly opposite” mean that when the tips of the expandable elements that are closest to each other during expansion are considered, the angle between the respective normals at each tip It means at least 135 °, preferably 160 °, more preferably 170 °, more preferably 175 °, most preferably 180 °.

  Conveniently, two cuff elements form the chamber and the opening is provided between the two cuff elements.

  The two cuff elements, the inflatable element, and the chamber formed by them are elongated, and the chamber is configured to accommodate a blood conduit longitudinally therein. The cuff element and the expandable element are preferably parallel to the blood conduit.

  Advantageously, the blood circulation assistance device further comprises an inlet leading to the two inwardly expandable elements.

  The inlet advantageously leads to the center of each inflatable element along the longitudinal axis.

  Alternatively, the inlet leads to one end of each inflatable element.

  Alternatively, the inlet leads to both ends of each inflatable element.

  Alternatively, the inlet leads to the side of the element along the entire length of each inflatable element.

  Preferably, the inlet is substantially parallel to the longitudinal axis of the inflatable element.

  Alternatively, the inlet makes an acute angle with the longitudinal axis of the expandable element.

  Alternatively, the inlet leads to the side of the element at a point between the center and end of the longitudinal axis of each inflatable element.

  Conveniently, the two inflatable elements are inflatable at the same time.

  It is preferable that the blood circulation assistance device further includes a manifold that communicates with the inflatable elements, and a cross section of the manifold that communicates with each inflatable element is different.

  Advantageously, the opposing sides of the blood conduits contained in the chamber do not contact each other during maximum expansion of the two inflatable elements.

  Conveniently, upon maximum expansion of the expandable element, the minimum cross-sectional curvature of the blood conduit contained in the chamber is maximized, the minimum cross-sectional curvature radius being at least 30% of the original value, for example Preferably it is at least 36.3% of the original value or exactly 36.3%. It is particularly preferred that the minimum cross-sectional radius of curvature is at least 40.4% or exactly 40.4% of the original value.

  The reduction in lumen cross-sectional area of the blood conduit contained in the chamber upon maximum expansion of the two inflatable elements is preferably at a rate exceeding 50% of the original value, 51 of the original value. More preferably, the ratio exceeds 5%.

  It is preferred that the vascular lumen gap during compression is at least 10% of the resting diameter, more preferably at least 15%, more preferably at least 20%. In this respect, of course, the blood circulation assisting device can be set so that the lumen gap is 20% of the initial alignment when the blood vessel is compressed. The cavity gap may change to, for example, 15% or 10% over time.

  The inflatable element is advantageously made of a material that resists elastic deformation.

  Conveniently the ends of the inflatable element are rounded.

  Both ends of the inflatable element preferably project longitudinally from the one or more cuff elements along the axis of a blood conduit housed in the chamber.

  Advantageously, the blood circulation assist device further comprises a pump in fluid communication with the inflatable element.

  Conveniently, the fluid path from the pump to the inflatable element increases in cross-sectional area.

The fluid communicating between the pump and the expandable element has a viscosity of 8 × 10 ^{−4 to} 1.2 × 10 ⁻³ Pa. s (0.8 to 1.2 cP), preferably 1 × 10 ⁻³ Pa.s. More preferably, it is s (1.0 cP).

  The fluid communicating between the pump and the expandable element is advantageously fluorocarbon.

  Conveniently, the connection provided between the pump and the inflatable element for fluid communication is flexible.

  Preferably, the flexible coupling part comprises a joint having a ball with a passage extending therein and rotatably connected to both ends of the socket.

  Advantageously, the flexible connection is concertinaed in order to obtain flexibility.

  Conveniently, the flexible connection can be locked in a specific arrangement.

  Preferably, the pump is adjacent to the one or more cuff elements, and the opening is provided on the opposite side of the chamber from the cuff.

  Advantageously, the pump is adjacent to the one or more cuff elements and the opening is provided at a 90 ° position on the chamber relative to the pump.

  The pump has an impeller that can rotate around an axis to provide a pumping action, and the impeller moves axially from a first position to a second position to reverse the direction of the pumping action. It is convenient to be able to.

  The blood circulation assistance device further includes a counterbalance, and the balance weight moves in a direction opposite to the axial movement of the impeller in synchronization with the impeller and antagonizes the reaction of the movement of the impeller. It is preferred that it be possible.

  The counterweight is advantageously movable in parallel with the impeller.

  Conveniently, the counterweight has a second rotatable impeller, both of which can rotate about an axis to provide pumping action.

  The blood circulation assistance device includes a sensor capable of detecting that the impeller is in the first position or the second position, and that the impeller is locked at a position that causes expansion of the expandable element. It is preferable to further include a control mechanism for shutting down the impeller in response to detection by the sensor.

  The pump includes a rotatable impeller, an inlet for suctioning fluid, an outlet for discharging fluid, and a valve assembly provided between the rotatable impeller and the inflatable element. The valve assembly is slidable or rotatable from a first position where the inlet is in fluid communication with the inflatable element to a second position where the outlet is in fluid communication with the inflatable element. Advantageously, the inflatable element is configured to contract and expand, respectively, as the valve assembly moves between a first position and a second position.

  Conveniently, the pump can be placed in the thoracic cavity.

  Alternatively, the pump can be placed in the pre-peritoneal or abdominal cavity and connected to the inflatable element via a hydraulic tube. The preperitoneal cavity can be formed by the surgeon.

  Alternatively, the pump can be installed outside the body.

  Advantageously, a flow guide is provided between the pump and the inflatable element. The flow guide is preferably a vane, swivel and / or deswirlers. The flow guide preferably minimizes undesirable secondary flow behavior or provides desirable secondary flow characteristics.

  It is preferable that the blood circulation assistance device further includes a sleeve provided on an outer periphery of the one or more cuff elements.

  Advantageously, the blood circulation assistance device further comprises at least one band around the one or more cuff elements.

  Conveniently, the one or more cuff elements are movable so as to increase or decrease the size of the chamber.

Preferably there are two or more cuff elements connected by a lockable hinge.
Advantageously, the blood circulation assisting device further comprises an inner sleeve placed between the inflatable element and the chamber.

  Conveniently, the blood circulation assisting device further comprises one or more small holes for attaching the device itself to the structure.

  The expandable element preferably has a length of 3 to 15 cm, more preferably 5 to 9 cm.

  Advantageously, the inflatable element is inflatable once in each cardiac cycle of the patient wearing the device.

  Conveniently, the inflatable element can be inflated at diastoles of each cardiac cycle of the patient wearing the device, or less frequently (eg, alternative cardiac cycles).

  The device is preferably installable in a human left paravertebral gutter.

  Advantageously, the blood circulation assistance device further comprises one or more integrated ECG electrodes for detecting the heartbeat of the individual.

  Conveniently, the blood circulation assistance device further comprises a position sensor, pressure sensor or accelerometer for detecting the heartbeat of the individual.

  The invention, in a further aspect thereof, is a blood circulation assistance device having one or more cuff elements forming a chamber for containing a blood conduit, wherein the one or more cuff elements are blood contained in the chamber. An inwardly expandable element for compressing the conduit, the expandable element being expandable to maximize a minimum cross-sectional radius of curvature of the blood conduit contained in the chamber upon maximum expansion. A blood circulation assist device is provided.

  Conveniently, the minimum cross-sectional radius of curvature of the blood conduit is at least 30% of the original value, preferably at least 36.3% or exactly 36.3%, at least 40.4% or exact More preferably, it is 40.4%.

  Upon maximum expansion of the expandable element, the reduction in lumen cross-sectional area of the blood conduit is preferably greater than 50% of the original value, and preferably greater than 51.5%.

  Advantageously, the lumen of the blood vessel during compression is at least 10% of the resting diameter, preferably at least 15%, more preferably at least 20%.

  In another aspect thereof, the present invention is a blood circulation assistance device having one or more cuff elements forming a chamber for containing a blood conduit and a pump, wherein the one or more cuff elements are disposed in the chamber. An inwardly expandable element for compressing a contained blood conduit, the pump comprising a rotatable impeller, an inlet for suctioning fluid, and an outlet for discharging fluid A valve assembly disposed between the rotatable impeller and the inflatable element, the valve assembly from the first position where the inlet is in fluid communication with the inflatable element. Is slidable or rotatable to a second position in communication with the inflatable element, and each of the inflatable elements is retracted by moving the valve assembly between a first position and a second position. And providing a blood circulation assisting device configured to expand.

  In yet another aspect thereof, the present invention provides a blood circulation assistance device having one or more cuff elements forming a chamber for containing a blood conduit and a pump, wherein the one or more cuff elements are the chambers. An inflatable inflatable element for compressing a blood conduit contained therein, the pump being in fluid communication with the inflatable element and capable of rotating about an axis to provide a pumping action The impeller can move in the axial direction from the first position to the second position to reverse the direction of the pumping action, and is further provided with a balance weight, Provides a blood circulation assistance device that can move in the direction opposite to the axial movement of the impeller in synchronization with the impeller and antagonize the reaction of the movement of the impeller.

  Conveniently, the blood circulation assisting device further comprises a second inward-expandable inflatable element for compressing a blood conduit housed in the chamber.

  In a further aspect thereof, the present invention is a method for counterpulsation of a blood vessel, comprising introducing an annular stent into the lumen of the blood vessel at each end of the portion of the blood vessel, and each of the portions of the blood vessel. Providing an outer band around the blood vessel at the distal end such that a portion of the blood vessel is trapped between each outer band and the respective annular stent; Performing a session.

  It is preferable to compress the blood conduit using the blood circulation assist device described above.

  Each annular stent advantageously has a circumferential groove on the outer surface of the stent for receiving a respective outer band.

  In this specification, “comprising” means “comprising” or “consisting of”, and “comprising” means “comprising” or “consisting of”.

  As used herein, “blood conduit” means a native blood vessel, a synthetic or artificial blood vessel, or other tubular structure for carrying blood.

  In order to minimize the risk of aortic trauma, the following were considered when designing embodiments of the present invention.

  1. The contralateral contact of the aortic endothelium (i.e., contact on the opposite side) has been found to be involved in endothelial detachment and atherogenesis, thus preventing contralateral contact when the aorta is fully compressed.

  2. In order to minimize the aortic wall stress, the maximum cross-sectional curvature of the aorta during compression is minimized (ie, the minimum cross-sectional radius of curvature is maximized) (FIG. 2).

  3. Avoid abrupt changes in the longitudinal section of the aorta at both ends of the peri-aortic jacket to minimize stress concentrations at both ends of the jacket (FIG. 3).

  4). It ensures that the shape of the aorta during deformation can be predicted reliably (ie avoiding creasing of the aortic wall and concomitant wall stress concentration).

  5. Minimize the relative movement of the jacket around the aorta relative to the aorta to avoid aortic folds.

  6). Minimize the transverse reaction to the aorta induced by the operation of the counterpulsator during the compression and release periods.

  In order that the present invention may be more readily understood and further features of the invention may be understood, embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which:

  As shown in FIG. 1, the blood circulation assistance device 1 has a pump or energy converter 2 connected to a hollow peri-aortic jacket or cuff 3. The peraortic cuff 3 is rigid or semi-rigid and is curved to form a substantially cylindrical chamber therein. Two elongate inflatable elements 4 and 5 are provided in contact with the inner surface of the peri-aortic cuff 3, which are held in place opposite to each other by the peri-aortic cuff 3 across the chamber. ing. The chamber size and shape are configured to (preferentially) accommodate the descending aorta 6 (however, in other embodiments, the chamber size and shape are configured to accommodate the ascending aorta. ), The inflatable elements 4, 5 are parallel to the descending aorta 6 and on the opposite side of the aorta 6. Each end of the chamber is open so that the aorta 6 extends through it. The peraortic cuff or jacket 3 is provided with a slit (or opening) 22 that communicates between the two inflatable elements into the chamber and extends from one end of the chamber to the other. The peripheral aortic cuff 3 is configured to slide on the aorta 6 in a direction perpendicular to the longitudinal axis of the aorta 6. Thereby, the apparatus 1 can be installed without requiring cutting of the aorta 6 (that is, surgical division).

  The inflatable elements 4, 5 are filled with a hydraulic drive medium contained within a normal low compliance manifold 7 and are in fluid communication with the pump or energy converter.

  The working fluid flow path between the pump and the inflatable elements 4, 5 minimizes flow resistance due to cross-sectional changes, as much as practicable, and undesired secondary flow characteristics of the hydraulic drive fluid ( For example, the fluid filling and draining of the inflatable elements 4 and 5 can be minimized by minimizing the counter-rotation associated with abrupt cross-sectional changes that can interfere with the filling and draining of fluid in the inflatable elements 4 and 5 Designed to be done quickly. However, the secondary flow characteristics are not necessarily harmful, but in practice, for example, a flow guide for mixing fluids to avoid simultaneous two-way flow in the hydraulic fluid path is provided, It may be desirable to enhance flow characteristics.

  When the hydraulic drive medium flows from the energy converter 2 into the manifold 7, the expandable elements 4 and 5 expand. When the outer surfaces of the inflatable elements 4, 5 are compressed by the peraortic cuff 3, the inner surfaces of the inflatable elements 4, 5 move together and compress the aorta within the jacket 3. The length of the aortic perimeter jacket 3 is preferably in the range of 3-15 cm.

  In vitro and animal experiments have shown that the pre-systolic arterial pressure drop is more pronounced when using a relatively short peri-aortic jacket (5 cm) compared to intra-aortic balloons (see FIG. 19). The degree to which the presystolic pressure is reduced by the counterpulsation device is very important in determining clinical efficacy, especially in the case of heart failure.

  When compressing the aorta, two types of conditions must be avoided: i) contact between the endothelium-to-surface and ii) excessive bending of the aortic endothelium. Both of these conditions result in endothelial damage and denudation, a process that is considered atherogenic. From our experimental studies, in a preferred embodiment, by selecting the size and position of the two inflatable elements 4, 5 (more inflatable elements to derive the same hemodynamic benefit) It has been found that the aorta is reliably deformed even when the maximum cross-sectional aortic curvature is relatively low (compared to the system with Our animal experiments have shown that it is relatively easy to place a peraortic jacket with two inflatable elements in the aorta.

  In embodiments where two inflatable elements 4, 5 are provided, it is important that the two elements inflate at the same time in order to avoid potentially harmful reactions on the aorta 6. Such simultaneous expansion can be achieved by designing a differential cross section of the manifold branch that provides the individual inflatable elements. When the expandable element is fully expanded, a gap is created between the inner surfaces of the expandable element as shown in FIGS. This gap is large enough to prevent contralateral contact of the aortic endothelium to minimize the risk of aortic endothelium detachment (ie, a highly atherogenic process). This gap is maintained by using an inflatable element that does not undergo significant elastic deformation under certain operating conditions, or by limiting the amount of hydraulic fluid within the system.

  Our experiments (see Example 2) showed that the optimal number of inflatable elements was two.

The inflatable elements 4, 5 in combination with the peraortic cuff or jacket 3 are relatively low compliant and therefore do not undergo significant elastic deformation when inflated, maximizing mechanical fatigue life. Nonetheless, a low degree of creep is expected in the inflatable element as the expansion / contraction cycle is repeated with the above-described sufficient lumen clearance. Acceptable mechanical fatigue life is obtained by appropriate selection of materials and wall thickness. By forming the inflatable element from a reinforced polymer or a filled polymer, the appropriate physical properties of the element could be obtained. The drive fluid used is not associated with undesired changes in the physical properties of the expandable element membrane over time. A potentially suitable driving fluid has a viscosity of 0.8 cP to 1.2 cP, preferably 1.0 cP (8 × 10 ⁻⁴ Pa.s to 1.2 × 10 ⁻³ Pa.s, preferably 1 × 10 ⁻³ Pa.s) aqueous liquid and non-aqueous liquid. In some embodiments, the drive medium is fluorocarbon.

  In order to further reduce the risk of aortic injury, the ends of the inflatable elements 4, 5 are rounded so that the ends protrude slightly from the rigid aortic cuff or jacket 3 in the longitudinal direction. Avoid abrupt changes in the cross section of the aorta at both ends of the jacket around the aorta (see FIGS. 1 and 3).

  According to the inventors' in vitro experiments, when two long inflatable elements 4, 5 provided parallel to the longitudinal axis of the aorta 6 were used, a circumferential cuff (in the case of the cuff) It has been found that the deformation characteristics of the aorta are more predictable compared to the usual aortic creasing and local stress concentrations that have been shown by our studies. Thus, the preferred embodiment is inherently more suitable for long-term counterpulsation than a transverse, circumferential peraortic cuff for aortic durability.

The relative position of the energy converter and the cuff Numerous advantages are obtained by reliably minimizing the distance between the cuff 3 around the aorta and the energy converter 2.
i) Reducing the overall size of the device reduces surgical trauma during implantation.
ii) Both “dead space” and flow resistance in the hydraulic fluid path are minimized. This is particularly important in the context of diastolic counterpulsation, a very dynamic process. Both the flow resistance of hydraulic fluid and the rate of change of flow over time (dQ / dt) are both adversely affected by large dead space inertial effects.

  In a preferred embodiment, the fluid dead space is minimized by minimizing the distance between the energy converter 2 and the periaortic jacket 3. A particularly preferred embodiment of the blood circulation assist device is shown in FIG. 4, a cross-sectional view at the level of impeller ports 8 in fluid communication with the inflatable elements 4, 5. As can be seen from this figure, the cross section of the hydraulic fluid path is not uniform in order to avoid excessive flow resistance and changes in flow resistance.

  In one embodiment of the present invention, a flow guide is introduced into the hydraulic fluid path to minimize undesirable secondary flow behavior that can adversely affect flow resistance and thus dQ / dt. An example of undesirable secondary flow is counter-rotation characteristics that can occur when the cross-section changes rapidly. Conversely, in one embodiment, a flow guide is provided to provide the desired secondary flow characteristics. For example, the performance characteristics (dQ / dt) of the apparatus can be improved by a guide that promotes mixing and suppresses simultaneous bidirectional flow. The flow guide takes the form of vanes, swirlers or deswirlers in the fluid path.

  In one embodiment, the size and shape of the illustrated energy converter 2 and peri-aortic cuff 3 are adapted to the left pleural cavity. In designing a blood circulation assist device, a surgeon places the device in the left paravertebral gutter after placement of the cuff around the aorta. The feasibility of this approach overlaps the preferred embodiment boundary within the normal human left pleural cavity boundary (including the descending aortic boundary) by computed tomography (CT) as shown in FIG. Confirmed by computer-based fitting studies.

  The fluid connection between the pump or energy converter 2 and the inflatable elements 4 and 5 varies depending on the embodiment.

  In the embodiment shown in FIG. 6, the manifold 2 connects the pump 2 to the inflatable elements 4, 5 at the center of their longitudinal axis. The manifold 7 is perpendicular to the longitudinal axis of the inflatable elements 4, 5.

  In the embodiment shown in FIG. 7, the manifold 7 is connected to the inflatable elements 4, 5 at 9, 10, one end of these elements. The direction of the manifold 7 forms an acute angle with the elongated inflatable elements 4, 5, and the fluid moves to the back of the manifold 7 as it moves from the pump to the inflatable elements 4, 5, or vice versa. It is configured to reflect back from the far wall 11.

  In the embodiment shown in FIG. 8, the inlet 7 is located in the middle of the inflatable elements 4, 5 along its longitudinal axis and perpendicular thereto. The manifold 7 branches into first and second ducts 12 and 13. A first duct connects the manifold 7 to the respective first ends 9, 10 of the expandable elements 4, 5, and a second duct 13 connects the manifold 7 to each of the expandable elements 4, 5. Connected to the second ends 13, 14. Thus, the pump 2 is in fluid communication with each end of each of the inflatable elements 4, 5.

  In the embodiment shown in FIG. 9, the manifold 7 is positioned perpendicular to the axis at the center of the longitudinal axis of the inflatable elements 4, 5, as in the above-described embodiment. However, in this embodiment, the manifold 7 is connected to both sides along the entire length of the elongated inflatable elements 4, 5.

  In the embodiment shown in FIG. 10, as in the embodiment shown in FIG. 7, the manifold 7 is provided at the first end 9, 10 of each of the inflatable elements 4, 5. However, in this embodiment, the manifold 7 is substantially parallel but offset with respect to the longitudinal axis of the inflatable elements 4, 5, so that the main portion of the manifold 7 and the inflatable elements 4, 5 respectively The “dog leg” portion 15 of the manifold 7 is present between the first ends 9 and 10.

  In each of the embodiments shown in FIGS. 6-11, the manifold 7 is placed equidistant from the two inflatable elements 4, 5. However, in the embodiment shown in FIG. 11, the manifold 7 is located between the center of the longitudinal axis of the inflatable elements 4, 5 and the first ends 9, 10 of the inflatable elements 4, 5. . The manifold 7 is substantially perpendicular to the longitudinal axis of the inflatable elements 4, 5.

  In order to accommodate slight anatomical differences between patients, in some embodiments, a universal coupling is provided between the energy converter 2 and the peri-aortic cuff 3 to reduce the displacement of the cuff. It is definitely avoided. Such deviations may reduce the effectiveness of counterpulsation for the following two reasons, and may increase the risk of aortic trauma due to increased local aortic wall stress: Not desirable.

  As shown in FIGS. 12 and 13, the universal joint 16 has a “ball and double socket” joint. More specifically, the universal joint 16 has first and second generally cylindrical portions 17, 18 connected by a ball 19 having a hole 20 therein. The first and second portions 17 and 18 are each turnable with respect to the ball 19 so that relative movement is possible. The first portion 17 and the second portion 18 are in fluid communication with the hole 20.

  14 and 15, the universal joint 16 has first and second substantially cylindrical portions 17, 18, and the first and second substantially cylindrical portions 17, 18. Are connected by a concertinaed section 21 which is sufficiently flexible so that they can move relative to each other.

  In some embodiments, for example, the movement of the universal joint shown in FIGS. 12-15 is accomplished using key-ways that allow only one in-plane adjustment of the position of the cuff 3 relative to the energy converter 2. Restrict.

  If the volume changes due to such a universal joint, the effectiveness of the device is reduced due to delays in filling and discharging the fluid in the cuff, so the universal joint needs to be low in compliance. In a variant of the preferred embodiment, the universal joint can be tightly locked in a particular configuration in a manner most suitable for the patient's tissue, adjusted by the surgeon during implantation. In some embodiments, the surgeon locks the universal joint by tightening the threaded compression ring or grab screw during the implantation procedure to hold the implanted device in place.

  In a preferred embodiment, the pump 2 is placed so as to be adjacent to and parallel to the peri-aortic cuff 3. In some embodiments, as shown in FIG. 16, a slit 22 is provided on one side of the surface formed by the pump 2 and the peraortic cuff 3. That is, the slit 22 is directed post-medially. In another embodiment, as shown in FIG. 17, a slit 22 is provided on the far side from the pump 2 of the aortic cuff 3. That is, the slit 22 is directed antero-medially.

In order to maximize the effectiveness of stabilization counterpulsation of the energy converter-peraortic cuff assembly and to minimize the risk of aortic trauma, the positional stability of the peraortic cuff 3 relative to the aorta 6 is Most important. An important advantage of embodiments of the present invention is that the slit 22 in the periaortic jacket 3 allows the periaortic jacket to be quickly placed in the aorta 6 without the need for surgical aortic segmentation or cardiopulmonary bypass. However, when the aorta surrounding jacket 3 is installed in the aorta 6, it is important that the jacket 3 does not shift thereafter. In order to prevent such a shift, in some embodiments, the device 1 is fixed relative to the aorta 6.

  In some embodiments, after the aortic jacket 3 is installed in the aorta 6, a low-stretch inert sleeve made of a strong synthetic fiber such as polyester woven fabric, Dacron (registered trademark), or PTFE is attached to the outer periphery of the jacket. Provided. A sheet of such material is sewn into a sleeve shape by the surgeon. Also, in some embodiments, such a sleeve is preformed and the surgeon sutures the sleeve to both ends of the aorta 6.

  In a further embodiment, a high tensile ratchet plastic band (eg, a band made of nylon or other material) is provided on the outside of the periaortic jacket 3. In a variation of such an embodiment, an adjustable buckle is provided on the band to change the outer periphery of the band. In other variations, such bands are made of woven material and can be sutured by the surgeon. In some embodiments, both an inert sleeve and a plastic band are provided.

Adaptation to changes in aortic diameter (Accommodation)
An important advantage of embodiments of the present invention that preferentially adjust the size and shape to place a blood circulation assist device in the descending aorta is that the diameter change in the descending aorta is small compared to that in the ascending aorta. The effectiveness is predictable. However, it is important that the device can be effectively connected to the aorta regardless of the diameter of the aorta. In one embodiment, the outer edge of the peraortic cuff 3 abutting on both sides of the slit 22 is semi-rigid and slightly splayed under normal conditions. Thus, by properly forming the cuff so that the circumferential tension on the cuff 3 is weakened at rest (ie, before the device is switched on), the surgeon can have two inflatables. Elements 4 and 5 can be brought close to the desired degree. Since the diameter of the aorta can be measured by imaging before or during surgery, if the diameter of the jacket around the aorta 3 can be adjusted to increase discontinuously, optimal compression of the aorta is achieved while avoiding contralateral contact of the aortic endothelium. There will be a means to ensure.

  Such an advantage is that in another embodiment, the peraortic cuff 3 has one or two hinged jaws on which the inflatable elements 4, 5 are placed, This can be obtained in an embodiment where the jaws can be locked to a diameter suitable for the size of the aorta 6.

Aortic Reinforcement The surgeon implanting the device of the present invention may want the aortic adventitia (outermost layer) and the inflatable elements 4, 5 not to be in direct contact. To achieve this, a polyester woven (Dacron®) sleeve, PTFE sleeve, tissue engineered construct, or mobilized intercostal muscle or other self-organization (such as pericardium) is inflatable. Between the elements 4 and 5 and the chamber containing the aorta 6. The adjustable peri-aortic jacket 3 allows such integration in the implantation procedure.

  Under certain circumstances, if it is considered that the device 1 is at high risk of aortic dissection and / or detachment, two annular stents may be placed at both ends of the peri-aortic jacket to prevent propagation of the dissociation / detachment. It is introduced into the lumen of the aorta 6. External banding is applied around the aorta 6 at the position where each annular stent exists in the aorta 6. Thus, the aorta 6 is sandwiched between the inner stent and the outer outer band. This prevents the propagation of aortic dissection.

  In a preferred embodiment, each annular stent is provided with a circumferential groove along its edge to accommodate the aorta 6 when the external band is applied, and the aorta 6 is pushed into the groove. This helps keep the stent and outer band in place.

Stabilization of the energy converter In some embodiments, a small hole is provided on the outer surface of the energy converter 2 so that the blood circulation assistance device is a rigid structure within the thoracic cavity (eg, spine, ribs, intercostal muscle, cartilage). Alternatively, the transducer can be stabilized so that it can be sutured, wired or screwed into a semi-rigid structure.

Modification of Energy Converter It is preferable to minimize aortic trauma during operation of the blood circulation assistance device of the present invention. In an embodiment (detailed in WO-A-02 / 24254) in which the pump 3 has an impeller that rotates around an axis and moves axially to provide a reversal of pumping. It is preferable that a feature for avoiding a reaction force on the aorta 6 when the device is operated is obtained. In the case of the energy converter 2, the axial reactions due to the bi-axial translation of the impeller assembly during normal operation are small. Although this reaction can be transmitted to the aorta 6, it is believed that this action is not clinically important because the mass of the impeller assembly is small relative to the rest of the energy converter / cuff assembly 2, 3. However, it is possible that this reaction may have an undesirable effect on the aorta 6 and other organs. Thus, in one embodiment, the energy converter 2 has two impeller assemblies that simultaneously move toward or away from each other to eliminate axial reaction.

  In other variations, the reaction associated with the axial motion of the impeller assembly is removed by simultaneous electromagnetic drive motion in the opposite direction of the equivalent mass. Of course, the direction of motion of the equivalent mass need not be exactly the opposite direction if the motion has a component in the opposite direction.

  Solutions to such problems include energy converters that are composed of rotating impellers that do not linearly translate and change the direction of fluid flow with an axial reciprocating valve assembly or rotating valve assembly.

  With reference to FIGS. 22 and 23, an embodiment of an energy converter having an axial reciprocating valve assembly will be described.

  The energy converter 24 includes a first cylindrical coupling portion 26 that communicates with a cuff (not shown) as shown in FIG. 1 and a second cylindrical coupling portion 27 that communicates with a fluid reservoir (not shown). It comprises a substantially tubular housing 25 having The tubular housing is sealed at both ends. Inside the tubular housing 25 is provided an axially slidable tubular valve assembly 28 having a first opening 29 aligned with the first cylindrical coupling 26. Second and third openings 30, 31 are provided in the tubular valve assembly 28 so as to face the first opening 29 in the radial direction. The second and third openings 30, 31 are aligned along the axial direction, but not both the second and third openings 30, 31 when the tubular valve assembly 28 moves in the axial direction. The openings 30, 31 are spaced from each other so that either one is aligned with the second cylindrical link 27 (ie, not at least across the full width of both).

  Within the tubular valve assembly 28, a tubular manifold 32 is provided coaxially with respect to the tubular valve assembly 28 and the tubular housing 25. A manifold 32 forms a substantially cylindrical interior 33. A contraction inlet 34 and an expansion outlet 35 are provided on one side of the manifold 32, both of which are aligned with the first cylindrical connection 26. The size and location of the first opening 29 of the tubular valve assembly is such that the opening can be aligned with either one of the contraction inlet 34 and the expansion outlet 35 rather than both (ie, at least the full width of both). It is decided not to cross.

  On the opposite side of the manifold 33, an expansion inlet 36 and a contraction outlet 37 aligned with the second cylindrical connecting portion 27 are provided. The size and location of the second and third openings 30, 31 are such that when the first opening 29 is aligned with the contraction inlet 34, the third opening 31 is aligned with the contraction outlet 37. And the expansion inlet 36 is determined to be blocked by the valve assembly 28. On the other hand, when the first opening 29 is aligned with the expansion outlet 35, the second opening 30 is aligned with the expansion inlet 36 and the tubular valve assembly 28 blocks the contraction outlet 37.

  Driving fluid is provided to the enclosure formed by the cuff, the energy converter 24 and the fluid reservoir.

  A centrifugal impeller 38 is provided in the cylindrical inner portion 33, and the impeller 38 sucks the driving fluid into the axial inlet 39 and discharges the fluid at the edge 40 of the impeller 38. The edge 40 of the impeller 38 is aligned with the contraction outlet 37 on one side and the expansion outlet 35 on the other side.

  In use, the cuff bladder is deflated and the tubular valve assembly is in the first position shown in FIG. In this position, as indicated by an arrow 41, the impeller 38 causes the driving fluid to pass from the axial inlet 39 into the impeller 38 via the first cylindrical connecting portion 26, the first opening 29 and the contraction inlet 34. The fluid is sucked and discharged from the edge 40 of the impeller 38 to the driving fluid reservoir via the contraction outlet 37, the third opening 31, and the second cylindrical connecting portion 27. Thus, the drive fluid is pumped from the cuff bladder to the drive fluid reservoir.

  Pumping is continued in the same direction by impeller 38 (ie, from axial inlet 39 to edge 40), but the tubular valve assembly 28 is illustrated by an electromagnetic actuator (not shown) to reverse the direction of pumping. It moves in the axial direction to the second position shown at 23.

  In the second position, the driving fluid is sent from the second cylindrical connecting portion 27 to the axial inlet 39 of the impeller 38 via the second opening 30 and the expansion inlet 36. From there, the fluid is pumped out to the edge 40 of the impeller 38, through the expansion outlet 35 and the first opening 29, leading to the first cylindrical coupling 26 leading to the cuff bladder. To be discharged. Thus, the drive fluid is pumped into the cuff bladder as shown by arrow 42, and the bladder expands.

  The tubular valve assembly 28 is then returned to the first position shown in FIG. 22 by the electromagnetic actuator to re-contract the cuff bladder. Thus, the tubular valve assembly 28 reciprocates in the axial direction to alternately contract and expand the cuff bladder.

  An embodiment of an energy converter having a rotating valve assembly will be described with reference to FIGS. The same reference numerals are used for the same components as the embodiment shown in FIGS. Similar to the above-described embodiment, the energy converter 24 includes a substantially tubular housing 25 in which the first and second cylindrical coupling portions 26 and 27 are provided on opposite sides. A tubular valve assembly 28 is provided coaxially within the housing, the assembly including a first opening 29 that can be aligned with the first cylindrical connector 26 and a second cylindrical connector 27. And the second and third openings 30 and 31 that can be aligned with each other. However, in this embodiment, the second opening 30 and the third opening 31 are not aligned along the axial direction, but are offset from each other in the axial and circumferential directions, and the tubular valve assembly Rotating 28 aligns either the second opening 30 or the third opening 31, but not both, with the second cylindrical connector 27 (ie, at least both of them are fully aligned). Is not configured).

  Further, a fourth opening 43 is provided on the same side of the tubular valve assembly 28 as the first opening 29. Again, the first opening 29 and the fourth opening 43 are offset from each other in the circumferential and axial directions, and the rotation of the tubular valve assembly 28 causes the first opening 29 and the fourth opening. Either one of the portions 43, but not both, is configured to be aligned with the first cylindrical connector 26 (ie, at least both are not fully aligned).

  The arrangement of the openings 29, 30, 31 and 43 of the tubular valve assembly 28 is such that when the first opening 29 is aligned with the contraction inlet 34, the third opening 31 is aligned with the contraction outlet 37. The expansion outlet 35 and the expansion inlet 36 are configured to be blocked by the tubular valve assembly 28. Conversely, when the second opening 30 is aligned with the expansion inlet 36, the fourth opening 43 is aligned with the expansion outlet 35, and the contraction inlet 34 and the contraction outlet 37 are separated by the tubular valve assembly 28. Blocked.

  In the tubular valve assembly 28, the manifold 32 and the impeller 38 are provided coaxially with the assembly as in the above-described embodiment.

  In use, the tubular valve assembly 28 is in the first position shown in FIGS. In the first position, the first opening 29 is aligned with the first cylindrical connector 26 and the contraction inlet 34, and the third opening 31 is the contraction outlet 37 and the second cylindrical shape. It is aligned with the connector 27. Driving fluid is drawn into the axial inlet 39 by the impeller 38 via the first cylindrical connector 26, the first opening 29 and the contraction inlet 34. Next, according to the arrow 41, the driving fluid is discharged from the edge 40 of the impeller 38 through the contraction outlet 37, the third opening 31, and the second cylindrical connector 27 by driving the impeller 38. Thus, drive fluid is pumped from the cuff bladder in fluid communication with the first cylindrical connector 26 to a reservoir in fluid communication with the second cylindrical connector 27.

  When reversing the direction of pumping of the energy converter 24, if it is not necessary to reverse the direction of pumping of the impeller 38, an electromagnetic actuator (not shown) can be used to connect the tubular valve assembly 28 to FIGS. To the second position shown in FIG. In the second position, the fourth opening 43 is aligned with the first cylindrical connector 26 and the expansion outlet 35. Similarly, the second openings 30 and 31 are aligned with the expansion inlet 36 and the second cylindrical connector 27. Thus, the driving fluid is sent out from the second cylindrical connector 27 to the axial inlet 39 of the impeller 38 by the impeller 38 via the second opening 30 and the expansion inlet 36. From there, the fluid is pumped out to the edge 40 of the impeller 38, as indicated by the arrow 42, via the expansion outlet 35, the fourth opening 43 and the first cylindrical connector 26 (see figure). (Not shown). Accordingly, in the second position of the tubular valve assembly 28, the impeller 38 has the effect of delivering drive fluid to the bladder and inflating the bladder.

  The tubular valve assembly is then rotated and retracted back to the first position and the process is repeated.

  As can be appreciated, conceptually, the axial inlet 39 of the impeller 38 can be considered an “inlet” and the edge 40 of the impeller 38 can be considered an “outlet”. Thus, the embodiment of FIGS. 22-29 moves from a first position where the inlet 39 is in fluid communication with the cuff inflatable bladder to a second position where the outlet 40 is in fluid communication with the inflatable bladder. It consists of a movable valve assembly 28.

Fail Safe Characteristics of Energy Converter A potentially dangerous failure mode of the blood circulation assistance device 1 of the present invention is when the aorta 6 continues to occlude in the whole cardiac cycle and the left ventricular work increases. The pump according to the embodiment of the present invention has an impeller that can rotate around an axis and can move in the axial direction to reverse the pumping direction (detailed in WO-A-02 / 24254). ), Embodiments of the present invention have advantages with inherent fail-safe properties. When the impeller of the energy converter 2 stops rotating, the aortic pressure causes the working fluid to flow from the inflatable elements 4 and 5 to the energy converter reservoir. However, if the impeller continues to rotate due to the failure mode and the impeller assembly remains with aortic compression, the left ventricle will be adversely affected. In order to address this problem, some embodiments provide a sensor that detects the axial position of the impeller assembly. A control mechanism is provided for receiving input from the sensor. In response to the sensor detecting that the impeller has stopped moving in the axial direction, the control mechanism shuts down the power to the impeller at a position where the inflatable elements 4, 5 are filled. In one embodiment, the sensor is a Hall effect sensor that detects that one or more magnets of the impeller assembly are approaching.

21 Alternative Location of Energy Converter In the embodiment of the present invention shown in FIG. 21, the peri-aortic cuff 3 is secured to the descending aorta 6 while the energy converter 2 is placed in the abdominal cavity or pre-peritoneal cavity. The transducer is connected to the implanted aortic cuff 3 by a hydraulic tube 23. In a further embodiment of the invention, the energy converter 2 is installed outside the body.

Alternative location for the peri-aortic cuff In a preferred embodiment, a per-aortic jacket 3 is placed in the descending thoracic aorta 6. However, in other embodiments, the aortic perimeter jacket 3 is provided at other systemic arterial locations.

Power supply Power is supplied to the embedded component by one of the following two means.

1. Transcutaneous drive system (Driveline)
In some embodiments, an extra electrical cable is provided in the drive train to ensure continued power supply even if individual cables fail. A cable with high tensile strength and flexibility (eg, cadmium / copper multifilament system) is provided. In some embodiments, the drive system is also provided with a textured outer sleeve to promote tissue ingrowth and minimize the risk of infection. In certain embodiments, in addition to providing power, a conductor may be provided in the percutaneous drive system to allow the operator to adjust the operating characteristics of the blood circulation assist device (ie, counterpulsator), and Alarms and data can be sent to external controller / monitor.

2. Transcutaneous Inductive Coupling System (TETS)
In some embodiments, in addition to providing power, a telemetry link is also provided in the TETS system to allow the operator to adjust the operating characteristics of the counterpulsator and to send heart rate signals, alarms, and data to an external controller / monitor Can be sent to.

Controller In some embodiments, the blood circulation assist device 1 has an electronic controller that receives power from a transcutaneous drive system or TETS system. The controller has means for detecting heartbeats to ensure that the operation of the device is properly synchronized. In order to synchronize the operation of the device and the heartbeat, it may be necessary to detect an electrocardiogram (ECG) or use other methods (position sensor, pressure sensor, accelerometer, etc.). An arterial pulse wave can be used as a trigger. Where ECG monitoring is required for heart rate detection, in some embodiments, at least one ECG electrode is incorporated into the implanted component. In some embodiments, the ECG detector has integral defibrillation protection.

  The function of the energy converter 2 is adjusted by the controller. An alarm device (sound alarm device or vibration alarm device) can be provided in the controller to warn the patient of malfunction. The controller can be provided with a data logging facility. If the system has a percutaneous drive system, the controller may be internal or external. If the controller is in the body, it can be integrated with a TETS-based secondary coil or energy converter / peraortic jacket assembly.

Unlike implantable battery ventricular assist device support, counterpulsation support will be well tolerated even if interrupted for a short period of time. Thus, it is usually not necessary to provide an embedded rechargeable battery to supply power to the system when an external power source is unexpectedly or intentionally disconnected. However, in some embodiments, an implantable rechargeable battery is provided, for example, if a patient highly dependent on the continuous function of the counterpulsator wants to take a bath.

Alternative configuration of the peri-aortic jacket In some embodiments, the peri-aortic jacket 3 is provided with a single inflatable element 4, particularly for ease of manufacture. In such an embodiment, the aorta is squeezed between the inflatable element and a rigid or semi-rigid element facing surface that can be part of the peraortic jacket 3.

EXAMPLES The present invention will be further described below with reference to examples.

This data was obtained in a short-term pig model of counterpulsation using the energy converter described in WO-A-02 / 24254 and a prototype cuff designed as shown in FIG. The effectiveness of this prototype device was evaluated against a 40 cm ³ intra-aortic balloon of the same pig model.

  Arterial blood pressure and ultrasonic coronary blood flow in the proximal left anterior coronary artery were monitored continuously. A peraortic jacket was used as shown in FIG. Two types of cuffs were selected with an inflatable element length of 5 cm and 9 cm.

  For both 5 cm and 9 cm cuffs, the increase in diastolic pressure was found to be comparable to that for intra-aortic balloons (see FIG. 19). It has been found that afterload reduction is comparable, if not superior to that of intra-aortic balloons. For example, in the case of a 5 cm long jacket around the aorta, the end-diastolic pressure was reduced by 10 mmHg as compared to the intra-aortic balloon. In this typical device, the diastolic coronary blood flow increased by 50 mL / min, and a large blood flow reversal spike was induced in the diastole / contraction transition phase compared to unassisted beats, This provided strong evidence of effective left ventricular afterload reduction (see FIG. 20).

There was no indication of trauma to the aorta at the level of the peraortic jacket after a short-term (one day) experiment, but this was a study of extraaortic counterpulsation driven by long-term self-skeletal muscle (aortic myoplasty) (Aortomyoplasty)) Consistent with ⁷ histological findings.

  An experimental model study was conducted to realize the design specification criteria detailed above. In a preferred embodiment of the present invention, the inflatable element used two peri-aortic jackets, which in this case yielded more symmetric longitudinal aortic stress and strain characteristics and were induced by a counterpulsator. This is because the peak cyclic excursion of the aortic wall is low. This is a very important factor in determining the clinical effectiveness of counterpulsation, both from the viewpoint of the rate of change of the aortic blood flow over time (dQ / dt) and the mechanical fatigue of the aorta. A theoretical benefit is obtained. However, an important question was whether additional benefits could be obtained if the number of inflatable elements was increased from 2 to more. Investigations by the inventors suggest that this is not the case.

  30 to 33 are cross-sectional views of a model showing the case where the aorta is in the center of the jacket around the aorta (that is, when the deformation of the aorta is maximum). These were obtained by spraying aerosol onto a butyl rubber O-ring having a cross-sectional diameter and a ring inner diameter of 2 mm and 99.1 mm, respectively, and resting on A4 size graph paper. A state 44 (circular) and a deformed state 45 are shown. The rigid disk 46 having a diameter of 76.1 mm was pressed and deformed to simulate the action of the expandable element in the expanded state. The diameter ratio of the aorta / inflatable element was selected based on values that seemed practical from both the manufacture of the jacket and placement around the aorta. The ratio was relatively unaffected.)

  FIG. 30 shows the simulated aorta, showing a resting state and a state where the narrowest gap is compressed to 20% of the resting aortic inner diameter. In this deformation, the cross-sectional area was reduced to 51.5% of the original value. In this deformed aortic profile, the minimum cross-sectional radius of curvature was 18 mm (ie 36.3% of the resting radius). In conclusion, in this experiment, the effect of lumen pressure on the aortic wall profile was ignored, so the minimum cross-sectional radius of curvature was underestimated. As a result, in this model, a more elliptical aortic flexion occurred farthest from the point of contact with the inflatable element compared to that seen in vivo.

  In order to better realize aortic deformation by modeling the action of lumen pressure, the O-ring was suppressed with a bar 47 provided on the axis perpendicular to the movement of the inflatable element (see FIG. 31). In this case, the minimum cross-sectional curvature radius value was greater than 20 mm (ie, exceeded 40.4% of the resting radius).

  Figures 32 and 33 show the effect of motion on the three inflatable element designs. In FIG. 32, the lumen gap was maintained at 20% of the resting diameter, but the cross-sectional area was reduced to 41% of the original value, so that the minimum radius of curvature was 10 mm (ie, the resting radius of the resting radius). 20.2%), resulting in increased local aortic stress and strain. In the case of FIG. 33, the minimum radius of curvature (at the time of deformation) is equivalent to the value measured in FIG. 31, and the reduction of the cross-sectional area was suppressed to 54% of the original value.

  These findings indicate that a two inflatable element design is preferred over a design with three (or more) elements. Also, the two inflatable element design is less likely to interfere with other anatomical structures and is easier to install around the aorta than a three (or more) inflatable element system. There are also advantages. Our conclusions from clinical computer tomography data support this conclusion.

  Short-term animal experimental studies conducted by the present inventors (see Example 1) indicate that a peraortic jacket having two inflatable elements is relatively easy to install when implanted, and such The design showed no visual or histological aortic trauma.

Reference 1. Abou-Awdi NL, Frazier OH, The HeartMate: A left ventricular assist device as a bridge to cardiac transplantation, Transplantation Proceedings 1992; 24: 2002-2003.
2. Yacoub MH, Tansley P, Birks EJ, Banner NR, Banners, Khaghani A, Bowles C, Bowles C, A novel combination therapy to reverse end-stage heart failure New combination therapy to recover) .Transplantation Proceedings 2001 33 (5): 2762-4.
3. Rose EA, Gelijns AC, Moskowitz AJ et al., Long-term mechanical left ventricular assistance for end-stage heart failure New England Journal of Medicine 2001; 345 (20): 1435-1443.
4). De Vries WC, Anderson JL et al., Clinical use of the total artificial heart. New England Journal of Medicine 1984; 310: 273-278.
5. Moulopoulos SD, Topaz S, Tops S, Kolff WJ, Diastolic balloon pumping (with carbon dioxide) in the aorta-a mechanical assistance to the failing circulation Mechanical assistance for circulatory failure), American Heart Journal 1962; 63: 669.
6). Arafa, OE et al., Annals of Thoracic Surgery 1999; 67: 645-651.
7). Pattison CW, Cumming DVE, Williamson A et al., Aortic counterpulsation for up to 28 days using autologous latissimus dorsi in sheep Pulsation), J Thorac Cardiovasc Surg 1991; 102: 766-73.

FIG. 1 is a perspective view of a blood circulation assisting device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a cuff around the aorta installed around the aorta (a contracted state (left) and an expanded state (right)) in the embodiment of the present invention. FIG. 3 is a longitudinal cross-sectional view along the peri-aortic cuff and the aorta line AA (left) and line BB (right) in the embodiment of FIG. 2 with the inflatable element contracted. (Left) and inflated state (right). FIG. 4 is an axial cross-sectional view of a blood circulation assistance device according to another embodiment of the present invention. FIG. 5 is a perspective view of a blood circulation assistance device according to an embodiment of the present invention, in which illustrations of a human chest obtained by computed tomography are superimposed. FIG. 6 is a perspective view of a manifold and an inflatable element of a blood circulation assistance device according to another embodiment of the present invention. FIG. 7 is a perspective view of a manifold and an inflatable element of a blood circulation assistance device according to another embodiment of the present invention. FIG. 8 is a perspective view of a manifold and an inflatable element of a blood circulation assistance device according to another embodiment of the present invention. FIG. 9 is a perspective view of a manifold and an inflatable element of a blood circulation assistance device according to another embodiment of the present invention. FIG. 10 is a perspective view of a manifold and an inflatable element of a blood circulation assistance device according to another embodiment of the present invention. FIG. 11 is a perspective view of a manifold and an inflatable element of a blood circulation assistance device according to another embodiment of the present invention. FIG. 12 is a perspective view of the universal joint in the first position between the energy converter and the inflatable element of the blood circulation assistance device according to another embodiment of the present invention. FIG. 13 is a perspective view when the universal joint shown in FIG. 12 is in the second position. FIG. 14 is a perspective view of another universal joint in a first position between an energy converter and an inflatable element of a blood circulation assistance device in a further embodiment of the present invention. FIG. 15 is a perspective view when the universal joint shown in FIG. 14 is in the second position. FIG. 16 is a perspective view of a blood circulation assistance device in still another embodiment of the present invention. FIG. 17 is a perspective view of a blood circulation assistance device according to another embodiment of the present invention. FIG. 18 is a perspective view of the cuff and manifold around the aorta of the blood circulation assistance device used in Example 1 of the present invention. FIG. 19 is a graph showing arterial blood pressure versus time for a 50 mm long aortic jacket (upper) and a 40 cm ³ intra-aortic balloon (lower) (symbol: A = assisted pulsation, U = unassisted pulsation). ). Figure 20 is a graph of i) electrocardiogram (ECG), ii) instantaneous coronary blood flow (proximal left anterior descending coronary artery), and iii) arterial blood pressure versus time in a model with a 50 mm long peraortic jacket. These graphs were obtained simultaneously with an auxiliary ratio of 1: 2. A pulsation with assistance is represented by “A”, and a pulsation without assistance is represented by “U”. FIG. 21 is a perspective view of a blood circulation assistance device in a further embodiment of the present invention, showing the position within the human torso. 22 is a longitudinal cross-sectional schematic view of an energy converter in one embodiment of the present invention in an “cuff deflated” state with an axial reciprocating valve assembly. FIG. 23 is a schematic longitudinal cross-sectional view of the energy converter according to the embodiment shown in FIG. 22 in the “cuff expansion” state. FIG. 24 is a schematic cross-sectional view in the longitudinal direction in the “cuff deflated” state of an energy converter in accordance with another embodiment of the present invention having a rotating valve assembly. FIG. 25 is a schematic sectional view taken along line A-A ′ of FIG. 24. FIG. 26 is a schematic cross-sectional view taken along line B-B ′ of FIG. 24. FIG. 27 is a schematic longitudinal sectional view of the energy converter according to the embodiment shown in FIG. 24 in the “cuff expansion” state. 28 is a schematic cross-sectional view of the energy converter shown in FIG. 27 taken along line A-A ′. 29 is a schematic cross-sectional view of the energy converter shown in FIG. 27 taken along line B-B ′. FIG. 30 shows the results of examining the bending of the aorta when it is compressed with two inflatable elements using an experimental model. FIG. 31 shows the results of studying the bending of the aorta when an experimental model is used for compression with two inflatable elements and further compression is performed to model the effect of lumen pressure. FIG. 32 shows the result of examining the bending of the aorta when it is compressed with three inflatable elements using an experimental model. FIG. 33 shows the results of examining the bending of the aorta when it is compressed with three inflatable elements using an experimental model.

Claims (58)

  A blood circulation assistance device having one or more cuff elements forming a chamber for containing a blood conduit, the chamber being open at both ends of the one or more cuff elements, through which the blood conduit passes An opening is provided on one side of the one or more cuff elements between each end of the chamber for installing the one or more cuff elements around a blood conduit. The one or more cuff elements have two inwardly expandable inflatable elements for compressing the blood conduit, the inflatable elements being disposed diametrically opposite each other across the chamber apparatus.   The blood circulation assistance device according to claim 1, wherein two cuff elements form the chamber, and the opening is provided between the two cuff elements.   The two cuff elements, the inflatable element, and the chamber formed by them are elongated, and the chamber is configured to accommodate a blood conduit longitudinally therein. The blood circulation assisting device according to claim 2, wherein the cuff element and the inflatable element are parallel to the blood conduit.   The blood circulation assistance device according to claim 3, further comprising an inlet communicating with the two inwardly expandable elements.   5. The blood circulation assist device of claim 4, wherein the inlet leads to the center of each inflatable element along the longitudinal axis thereof.   The blood circulation assistance device according to claim 4, wherein the inlet leads to one end of each inflatable element.   The blood circulation assistance device according to claim 4, wherein the inlet leads to both ends of each inflatable element.   The blood circulation support device according to claim 4, wherein the inlet leads to a side surface of each inflatable element along the entire length thereof.   The blood circulation assist device of claim 6, wherein the inlet is substantially parallel to a longitudinal axis of the inflatable element.   The blood circulation assistance device according to claim 6, wherein the inlet forms an acute angle with respect to a longitudinal axis of the expandable element.   5. A blood circulation assist device according to claim 4, wherein the inlet leads to the side of the element at a point between the center and end of the longitudinal axis of each inflatable element.   The blood circulation assistance device according to any one of the preceding claims, wherein the two inflatable elements are inflatable simultaneously.   The blood circulation assistance device according to claim 12, further comprising a manifold leading to the inflatable element, wherein the cross section of the manifold leading to each inflatable element is different.   The blood circulation assistance device according to any one of the preceding claims, wherein the opposing side surfaces of the blood conduits contained in the chamber do not contact each other during maximum expansion of the two inflatable elements.   The maximum cross-sectional radius of curvature of the blood conduit housed in the chamber upon maximum expansion of the inflatable element, preferably the minimum cross-sectional radius of curvature is at least 30% of the original value, The blood circulation auxiliary device according to any one of claims.   Upon maximum expansion of the two inflatable elements, the reduction in lumen cross-sectional area of the blood conduit housed in the chamber is less than 50% of the original value, preferably less than 51.5% of the original value. The blood circulation auxiliary device according to any one of the preceding claims.   The blood circulation assistance device according to any one of the preceding claims, wherein the inflatable element is made of a material resistant to elastic deformation.   The blood circulation assistance device according to any one of the preceding claims, wherein both ends of the expandable element are rounded.   The blood according to any one of the preceding claims, wherein both ends of the inflatable element project longitudinally from the one or more cuff elements along the axis of a blood conduit contained in the chamber. Circulation assist device.   The blood circulation assistance device according to any one of the preceding claims, further comprising a pump in fluid communication with the expandable element.   21. The blood circulation assist device of claim 20, wherein a fluid path from the pump to the inflatable element increases in cross-sectional area. The fluid communicating between the pump and the expandable element has a viscosity of 8 × 10 ^{−4 to} 1.2 × 10 ⁻³ Pa. s (0.8 to 1.2 cP), preferably 1 × 10 ⁻³ Pa.s. The blood circulation assistance device according to claim 20 or 21, which is s (1.0 cP).   The blood circulation assistance device according to any one of claims 20 to 22, wherein the fluid communicating between the pump and the inflatable element is fluorocarbon.   The blood circulation assistance device according to any one of claims 20 to 23, wherein a connection portion provided between the pump and the inflatable element for fluid communication is flexible.   25. The blood circulation assisting device according to claim 24, wherein the flexible connecting portion includes a joint having a ball having a passage extending therein and rotatably connected to both ends of the socket.   The blood circulation assisting device according to claim 24, wherein the flexible connecting portion has a bellows shape to obtain flexibility.   27. The blood circulation assistance device according to any one of claims 24 to 26, wherein the flexible connecting portion can be locked in a specific arrangement.   28. A blood circulation assist according to any one of claims 20 to 27, wherein the pump is adjacent to the one or more cuff elements and the opening is provided on the opposite side of the chamber from the cuff. apparatus.   28. A pump according to any one of claims 20 to 27, wherein the pump is adjacent to the one or more cuff elements and the opening is provided at a 90 ° position of the chamber relative to the pump. Blood circulation assist device.   The pump has an impeller that can rotate around an axis to provide a pumping action, and the impeller moves axially from a first position to a second position to reverse the direction of the pumping action. The blood circulation assistance device according to any one of claims 20 to 29, which can be performed.   31. The balance weight according to claim 30, further comprising a balance weight, wherein the balance weight can move in a direction opposite to the axial movement of the impeller in synchronization with the impeller and antagonize a reaction of the movement of the impeller. Blood circulation assist device.   32. The blood circulation assistance device according to claim 31, wherein the balance weight is movable in parallel with the impeller.   33. A blood circulation assistance device according to claim 31 or 32, wherein the counterweight has a second rotatable impeller, and both impellers can rotate about an axis to provide a pumping action.   A sensor capable of detecting that the impeller is in the first position or the second position, and the sensor detecting that the impeller is locked at a position that causes expansion of the expandable element. 34. The blood circulation assistance device according to any one of claims 30 to 33, further comprising a control mechanism for shutting down the impeller accordingly.   The pump includes a rotatable impeller, an inlet for suctioning fluid, an outlet for discharging fluid, and a valve assembly provided between the rotatable impeller and the inflatable element. The valve assembly is slidable or rotatable from a first position where the inlet is in fluid communication with the inflatable element to a second position where the outlet is in fluid communication with the inflatable element. 30. Any one of claims 20-29, wherein the inflatable element is configured to contract and expand as the valve assembly moves between a first position and a second position, respectively. The blood circulation assist device according to 1.   30. The blood circulation assistance device according to any one of claims 20 to 29, wherein the pump can be installed in the abdominal cavity and is connected to the inflatable element via a hydraulic tube.   37. The blood circulation assistance device according to any one of claims 20 to 36, wherein a flow guide is provided between the pump and the inflatable element.   The blood circulation assistance device according to any one of the preceding claims, further comprising a sleeve provided on an outer periphery of the one or more cuff elements.   The blood circulation assistance device according to any one of the preceding claims, further comprising at least one band around the one or more cuff elements.   The blood circulation assistance device according to any one of the preceding claims, wherein the one or more cuff elements are movable to increase or decrease the size of the chamber.   41. A blood circulation assist device according to claim 40, wherein two or more cuff elements connected by a lockable hinge are provided.   The blood circulation auxiliary device according to any one of the preceding claims, further comprising an inner sleeve disposed between the inflatable element and the chamber.   The blood circulation assistance apparatus according to any one of the preceding claims, further comprising one or more small holes for attaching the blood circulation assistance apparatus itself to the structure.   The blood circulation assistance device according to any one of the preceding claims, wherein the expandable element has a length of 3 to 15 cm, preferably 5 to 9 cm.   The blood circulation assistance device according to any one of the preceding claims, wherein the inflatable element is inflatable once in each cardiac cycle of a patient wearing the device.   45. The blood circulation support device according to any one of claims 1 to 44, wherein the inflatable element is inflatable at a diastole of each cardiac cycle of a patient wearing the device or less frequently.   The blood circulation assistance device according to any one of the preceding claims, which can be placed in the left paravertebral groove of a human.   The blood circulation assistance device according to any one of the preceding claims, further comprising one or a plurality of integrated ECG electrodes for detecting the heartbeat of the individual.   The blood circulation assistance device according to any one of the preceding claims, further comprising a position sensor, a pressure sensor, or an accelerometer for detecting a heartbeat of the individual.   A blood circulation assist device having one or more cuff elements forming a chamber for containing a blood conduit, the one or more cuff elements being inwardly expanded to compress the blood conduit contained in the chamber A blood circulation assist device having a mold inflatable element, wherein the inflatable element is expandable to maximize the minimum cross-sectional radius of curvature of the blood conduit housed in the chamber upon its maximum expansion.   51. The blood circulation assist device of claim 50, wherein a minimum cross-sectional curvature radius of the blood conduit is at least 30% of an original value.   52. A blood circulation assist device according to claim 50 or 51, wherein upon maximum expansion of the inflatable element, the reduction in lumen cross-sectional area of the blood conduit is up to more than 50% of the original value.   A blood circulation assistance device having one or more cuff elements forming a chamber for containing a blood conduit, and a pump, the one or more cuff elements for compressing the blood conduit contained in the chamber The inflatable expandable element includes a rotatable impeller, an inlet for sucking fluid, an outlet for discharging fluid, the rotatable impeller and the expansion A valve assembly disposed between the first and second inflatable elements, the valve assembly from a first position where the inlet is in fluid communication with the inflatable element and a second outlet in communication with the inflatable element. Slidable or rotatable to a second position, and wherein the inflatable element is configured to contract and expand by moving the valve assembly between a first position and a second position, respectively. That blood circulation assist device.   A blood circulation assistance device having one or more cuff elements forming a chamber for containing a blood conduit, and a pump, the one or more cuff elements for compressing the blood conduit contained in the chamber The pump has an impeller in fluid communication with the inflatable element and capable of rotating about an axis to provide pumping action, the impeller comprising: The pump can move in the axial direction from the first position to the second position to reverse the direction of the pump action, and further provided with a counterweight, and the counterweight is synchronized with the impeller and the impeller A blood circulation assistance device that can move in the opposite direction to the axial movement of the impeller and antagonize the reaction of the movement of the impeller.   55. The blood circulation assist device according to any one of claims 50 to 54, further comprising a second inwardly expandable element for compressing a blood conduit housed in the chamber.   A method for counterpulsation of a blood vessel, comprising introducing an annular stent into the lumen of the blood vessel at each end of a portion of the blood vessel, and an external band around the blood vessel at each end of the blood vessel And allowing a portion of the blood vessel to be trapped between each outer band and a respective annular stent, and counterpulsing the vessel between two annular stents.   57. The method according to claim 56, wherein the blood conduit is compressed using the blood circulation assist device according to any one of claims 1 to 55.   58. A method according to claim 56 or 57, wherein each annular stent has a circumferential groove on the outer surface of the stent for receiving a respective outer band.

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